1. Field of the Invention
The present invention relates generally to devices for treatment of sleep disorders, and more particularly to an intraoral mandibular advancement device for the treatment of snoring, obstructive sleep apnea, gastroesophageal reflux disease, and bruxism and method for delivering the same.
2. Discussion of the Background
Among the health problems associated with sleep disorders are inter alia, snoring, gastroesophageal reflux disease (“GERD”), obstructive sleep apnea (“OSA”), bruxism, diabetes, high blood pressure (hypertension), and increased risk of stroke or heart attack.
The most widespread sleep disorder is snoring which is a common affliction that affects tens of millions of people worldwide, and can potentially have very serious health and social consequences. Snoring is a sound produced by the vibration of tissue caused by a breathing obstruction during sleep. There are many factors associated with snoring including, but not limited to: heredity, body weight, age, gender, smoking history, nasal, tonsil, or soft palate deformities, use of alcohol, allergies, and sleep position. Commonly, both the snorer and the snorer's sleep partner lose sleep due to the snorer's snoring. The sleep partner is awakened by the sounds caused by snoring, perhaps repeatedly each night. Movement by the sleep partner in subsequently attempting to fall back asleep may then awaken the snorer, if the noise of his or her own snoring has not already done so. Lack of sleep subsequently leads to daytime fatigue, a compromised immune system, poor mental and emotional health, irritability and lack of productivity, which can lead to further repercussions. Snoring is thus problematic for many people.
Obstructive sleep apnea is a potentially lethal sleep and breathing disorder defined as the cessation of breathing for 10 seconds or more (an apnea) at least five times per hour of sleep. In severe cases, individuals can wake up 300 times per night. When breathing is interrupted by an obstruction in the airway, the body reacts by waking enough to start breathing again. Arousals may occur hundreds of times each night, and may not fully awaken the individual, who remains otherwise unaware of the loud snoring, choking and gasping for air typically associated with OSA.
Although not all snorers have OSA, snoring is a cardinal symptom of OSA and clearly indicative of and associated therewith. Many OSA sufferers do not receive a sufficient amount of sleep due to repeated apneatic events and arousals which act to prevent REM and deep stage sleep, which can lead to chronic daytime exhaustion and long-term cardiovascular stress. OSA is the direct cause of at least 38,000 deaths each year. An estimated 30 million Americans suffer from some degree of OSA, yet less than 3% are currently undergoing any type of treatment.
Pathogenesis of OSA involves a combination of reduced upper airway size and altered upper airway muscle activity, which causes oral tissue to collapse, and hence a blockage to occur. Other factors which are thought to contribute to OSA include tongue size, soft palate volume, a retrognathic mandible, an anteroposterior discrepancy between the maxilla and the mandible, and obesity.
Snoring and OSA are often associated, as generally both are caused by blockage of the pharyngeal airway by, for example, excess tissue when various muscles of the body, including the tongue, relax. As the tongue relaxes, it moves posteriorly, blocking the breathing airway. When the breathing airway is blocked, exhaled air is forced through the airway with increased velocity thereby causing vibration of the tongue, tissue, or other obstruction, thereby creating noise. Snoring is caused by the partial obstruction of breathing during sleep while OSA occurs when the tongue and soft palate collapse onto the back of the throat and completely block the pharyngeal airway, thereby stopping breathing during sleep and restricting the flow of essential oxygen. Thus, a correlation between snoring and OSA is generally recognized in the medical community.
Many attempts have been made to reduce or eliminate snoring and OSA in individuals. Various types of surgery, including tracheostomy, surgery of the soft palate and oropharynx, and reconstructive surgery have been utilized in the treatment of snoring and OSA. Invasive surgery however is costly and not without risk, which effectively eliminates this modality as a truly viable solution to snoring and OSA for the general population. Indeed, many practitioners and patients alike would generally seek to avoid surgical intervention and would welcome a minimally invasive route—a general object and feature of the instant invention.
It has been recognized that opening or enlarging an airway that may be constricted due to collapse of tissue about the oropharynx will normalize the airflow to the lungs and in doing so will have a direct effect of resolving snoring and OSA as well as diminishing pressure fluctuations in the esophagus which have been associated with GERD. Known in the art are devices (heretofore cumbersome or ineffective) which are designed to restrict the velocity of the ingress and egress of air with the goal of reducing or eliminating snoring. It is scientifically concluded herein that by opening the aperture of the airway and maintaining the same, the consequences of a collapsed airway are avoided. When the airway is collapsed, the velocity of air flow increases and causes the vibration of the tongue, soft palate, and other tissue present in the pharyngeal wall during sleep. Thus, when expanded and maintained by the invention herein, the airflow is also maintained and snoring and OSA (where it theretofore resulted therefrom) are minimized or eliminated.
For example, U.S. Pat. No. 6,263,877 to Gall shows a device which essentially consists of a mouth guard with a small aperture for which are can pass through. The amount of air flow is therefore directly proportional to the size of the aperture. U.S. Pat. No. 5,642,738 to Lilly, Jr. shows a device which is designed to eliminate snoring via a membrane which is placed on the exterior surface of the anterior teeth to reduce the volume of air which is allowed to flow in and out of the mouth. U.S. Pat. No. 4,817,636 to Woods likewise shows a device which seeks to eliminate snoring via a membrane which is placed on the exterior surface of the anterior teeth to reduce the volume of air which is allowed to flow in and out of the mouth. Yet, reduction of airflow can cause a cascade of other symptomology and situations, including potential OSA.
Also known in the art are devices which seek to reduce or eliminate snoring or OSA by inhibiting vibration of the soft palate. For example, U.S. Pat. No. 6,467,485 to Schmidt shows a device made of a flexible material which is placed over the soft palate in an attempt to inhibit vibration of the soft palate. U.S. Pat. No. 4,669,459 to Spiewak shows an intraoral device which seeks to eliminate snoring by positioning a button on the soft palate to prevent vibration thereof. Yet, such devices do not address the source of the problem or intervene to increase the airway (as does the instant invention), and thus the cascade effect is still a present risk if such devices are employed.
Various devices have sought to alleviate snoring by aiming to keep the pharyngeal airway open to prevent the collapse of the tongue and soft tissues in the back of the throat, yet are bulky and uncomfortable, often resulting in reduced patient compliance. For example, U.S. Pat. No. 6,386,201 to Fard shows a pillow which seeks to keep the user's head in proper position to make snoring less likely. U.S. Pat. No. 4,366,815 to Broomes and U.S. Pat. No. 5,357,981 encompass other designs aimed at maintaining the user's body in a position which makes snoring less likely. U.S. Pat. No. 6,668,834 shows a device which seeks to eliminate or reduce snoring by maintaining the user's chin above the user's chest while in the supine position in order to facilitate breathing as well as to aid in the prevention of snoring.
Positioning of the body does not eliminate the cause of snoring. Since tongue posture appears to have a substantial effect on upper airway morphology, several devices show a design which seeks to hold the tongue in a forward position in order to increase the diameter of the pharyngeal airway during sleep. For example, U.S. Pat. No. 6,494,209 to Kulick shows a device which consists essentially of a mouthpiece with an anterior suction mechanism which creates a vacuum which acts to maintain the tongue in an anterior position. U.S. Pat. No. 6,408,851 shows a device which clamps the tongue in order to maintain the tongue in a forward position. U.S. Pat. No. 6,055,986 to Meade shows a device for the reduction of snoring which encompasses both upper and lower positions which together form a cavity which encompasses the user's tongue when in use to maintain the tongue in a predetermined position or to prevent the tongue from moving posteriorly and thus blocking the pharyngeal airway. U.S. Pat. No. 5,988,170 shows a snoring prevention apparatus consisting essentially of a mask having a tongue depressing member, which acts to maintain the tongue in an anterior position during use. U.S. Pat. No. 6,845,774 to Gaskell shows a mandibular splint which acts to maintain the user's jaws at a predetermined space apart to prevent the tongue from moving posteriorly in order to open the breathing passage. One can only image how truly uncomfortable such devices must be if used at all, and thus the likelihood of patient compliance is small to nil.
There is also recognition of those of ordinary skill in the art of a correlation between OSA and nocturnal gastroesophageal reflex disease (“GERD”). Both OSA and GERD involve a reduction in air pressure in the trachea and esophagus caused by blockage during sleeping, thereby resulting in an increase in the draw of pressure through the esophagus as the diaphragm distends. While the body tends to increase breathing by such distention, the blockage results in the pulling of fluid upwardly in the esophagus and hence results in GERD for the snorer or OSA patient. Yet, the currently recommended solutions involve some version of a “CPAP” (continuous positive airway pressure) or pharmacological intervention. The former involves a face mask and a pump to provide pressure directly to the trachea of the patient which is cumbersome and unaesthetic. The latter obviously includes a plethora of side effects associated with the pharmacology employed, while not directly addressing the physical/mechanical source of the problem.
It is herein recognized that advancing the mandible in an anterior position relative to the maxilla during sleep opens the pharyngeal airway by indirectly urging the tongue forward to stimulate activity of the muscles in the tongue and thereby also increases the forward rigidity of the tongue. Since the tongue attaches to the posterior portion of the mandibular symphysis, advancing the mandible forward relative to the maxilla also pulls the tongue forward, thus preventing the tongue from obstructing the pharyngeal airway. Since the palatoglossus muscle attaches from the tongue to the soft palate, resultant forward movement of the tongue thereby creates tension on the soft palate thereby reducing vibration. Mandibular advancement devices therefore function to move the lower jaw, and hence the tongue forward to open the oropharynx. Snoring thus decreases proportionally with the increase in airway size or diameter.
It should therefore be appreciated that by so urging, and as an object of the instant invention, there can be a positive effect on reduction of snoring and OSA, and also upon GERD which is associated with the existence of large intrapleural pressure swings, which occur during apneatic events.
A number of different appliances for the treatment of snoring or OSA which move the mandible forward relative to the maxilla have been suggested, yet such devices typically fit over both the arches of teeth and are thus large and cumbersome. Several such different devices allegedly for the treatment of snoring or OSA move the mandible forward relative to the maxilla can be observed in the following U.S. patents: Halstrom, U.S. Pat. No. 6,729,335; Thornton, U.S. Pat. No. 6,516,805; Orrico, U.S. Pat. No. 6,170,485; Belfer, U.S. Pat. No. 6,092,523; Bergersen, U.S. Pat. No. 6,129,084; Fenton, U.S. Pat. No. 5,499,633; Tomasi, U.S. Pat. No. 5,313,960; Hays, U.S. Pat. No. 5,277,202; Shapiro, U.S. Pat. No. 5,177,816; and Strong, U.S. Pat. No. 6,526,982. These devices consist essentially of acrylic or elastomeric upper and lower bite trays which fit over both the maxillary and mandibular teeth, respectively, with some connecting means to shift the user's bite so that the mandible is urged forward relative to the maxilla. Thus, to achieve anterior movement of the mandible, these devices essentially move one jaw against the other in a cumbersome manner which no doubt has an effect on patient compliance.
Such appliances which fit over both arches of teeth were derived from the orthodontic domain which it has ordinarily been considered prudent to cover all the teeth in order to prevent undesired movement (eruption) of any teeth not covered by the device resulting from a lack of opposition. Studies have shown however that partial coverage of the teeth during sleep does not result in undesired eruption of uncovered teeth, therefore rendering previous concerns unwarranted. These devices are therefore unnecessarily bulky and difficult to fit over the user's teeth. Bulky devices also occupy a large portion of the oropharyngeal volume, thus making breathing, and the passage of air around the bulky device difficult—the very antithesis of the goal herein sought: to increase the dimensional size of the airway. Breathing difficulty substantially reduces the efficacy of such devices to treat snoring or OSA, let alone the secondary effects of GERD caused by airway obstruction.
Many devices claimed for treatment of snoring or OSA which move the mandible forward relative to the maxilla fit over both the arches of teeth and also move one jaw substantially against the other, thereby posing other potentially damaging effects. Mandibular advancement devices that fit over both the maxillary and mandibular teeth are typically held nearly stationary, thereby restricting movement, causing discomfort, and potential permanent repositioning of the jaw. Since these types of devices restrict the user's natural lateral movements as well as anterior and posterior movements, continued use can potentially aggravate the tempromandibular joint (TMJ) and the related facial musculature, which would worsen over time, with continued use. Thus, it is an object of the instant invention to permit such movements, increase comfort and compliance, and additionally avoid TMJ effects.
Also shown in the art are appliances which are worn only upon the user's maxillary teeth, thus leaving the mandibular teeth uncovered. For example, U.S. Pat. No. 5,915,385 to Hakimi discloses a snore and stress relief device which seeks to engage the user's upper dentition and includes an anterior extension which appears to advance the user's lower jaw forward with respect to the user's upper jaw such that the user's upper airway is enlarged and the passage of air through the upper airway is facilitated. The device disclosed in Hakimi has a posterior position which fits against the dorsal surface of the user's soft palate to secure the device, which may also cause gagging or other discomfort, thus reducing or eliminating efficacy.
Although prior devices may have effect in treating snoring and OSA by moving the mandible forward relative to the maxilla to open the airway, such devices have unwanted side effects or are ineffective due to, inter alia, their bulk. As stated herein, many of the devices which appear to be designed to alleviate snoring and OSA restrict the user's natural nocturnal movements of the lower jaw which can potentially aggravate the tempromandibular joint and related jaw muscles and ligaments. Due to their bulk, devices prior to that shown herein that claim a design to eliminate or reduce snoring or OSA rely largely on the user's ability to breath through the nose. Thus, such devices would not function properly with users who have difficulty breathing through their noses. Furthermore, many of these devices must be removed or unhinged or otherwise disengaged to allow the user freedom to speak, swallow, or drink water, thus creating serious inconvenience to the user (and poor aesthetics). It is thus an object of the instant invention to overcome these shortcomings in prior devices.
Gastroesophageal reflex disease (“GERD”), also known as acid reflux, is a chronic condition which affects at lest 5 to 7% of the global population, including over seven (7) million people (reportedly as high as 30 million) in the United States alone. GERD is characterized by movement of the liquid contents of the stomach from the stomach into the esophagus. Almost everyone experiences gastroesophageal reflux at some time or another. When reflux is frequent or severe enough to cause more significant problems, it is characterized as GERD. GERD can cause serious complications including inflammation of the esophagus from stomach acid that causes bleeding or ulcers. Asthma, chronic cough, and pulmonary fibrosis may be aggravated or even caused by GERD.
The liquid content of the stomach typically contains acid, pepsin, and bile, which are harmful to the delicate lining of the esophagus when regurgitated. Damage to the esophageal lining can result in scarring and narrowing of the esophagus, and can be linked to the development of esophageal cancer.
Pressure created by the lower esophageal sphincter (“LES”) and diaphragm surrounding the LES ordinarily create a barrier to reflux. During snoring or an apneatic event, however, a large negative intrapleural pressure swing often occurs facilitating reflex events. Thus, blockage of the esophageal airway creates a negative pressure which allows reflux to occur by facilitating the upward movement of the liquid contents of the stomach. When in an upright position, most refluxed liquid naturally flows back into the stomach due to the force of gravity. When in a supine position however, most refluxed liquid is forced upwardly, into the esophagus, typically causing damage thereto. Due to the increased potential for reflex during sleep in the supine position, it is therefore beneficial to have a method of treatment which can be applied during sleeping hours to maintain the pressure system without creating negative esophageal pressure and concomitant potential reflex. See, e.g., Green, B T, et al., Marked Improvement in Nocturnal Gastroesophageal Reflux in a Large Cohort of Patients with Obstructive Sleep Apnea with Continuous Positive Airway Pressure, Arch. Intern. Med., 2003 Jan. 13; 163(1):41-5.
Symptoms of gastroesophageal reflux disease include regurgitation, heartburn, difficulty swallowing, chest pain and nausea. As a chronic disease, treatment of gastroesophageal reflux disease typically continues indefinitely. It is therefore preferable that a method of treatment for gastroesophageal reflux disease is comfortable for nightly use.
Among the heretofore shown methods used to treat GERD are the use of antacids, histamine antagonists, proton pump inhibitors, promobility drugs which stimulate the muscles of the gastrointestinal tract, foam barriers which form a physical barrier to the reflux of liquid, and surgery. For example, U.S. Pat. No. 6,979,750 to Scanlan et al. shows thyronamine derivatives and analogs for the treatment of GERD. U.S. Pat. No. 6,974,837 to Jerussi et al. shows pharmaceutical compositions that comprise a racemic or optically pure sibutramine metabolite and a phosphodiesterase inhibitor for the treatment of GERD. U.S. Pat. No. 6,548,518 to Rubin et al. shows the use of norcisapride in combination with proton pump inhibitors or H2 receptor antagonists for the treatment of GERD.
Continuous Positive Airway Pressure (“CPAP”) therapy has been shown to reduce GERD by increasing intra-esophageal pressure. Yet these devices have drawbacks, as herein stated, and thus are not of choice especially if non-invasive, easily placeable and removable, and not uncomfortable alternatives, like that of the instant invention, are available. Although there exists a broad range of dentally-retained intraoral appliances worn at night for the treatment of snoring and obstructive sleep apnea, no such appliances heretofore satisfied such criteria and, also, were directed at treatment of GERD. It is thus an object of the instant invention to present a noninvasive alternative to drug therapy and surgical intervention for the treatment of GERD.
Bruxism is the technical description for clenching, gnashing or grinding of teeth. Bruxing is common in almost all individuals and can occur subconsciously or when an individual becomes stresses or aggravated. The risk of bruxism increases with age, stress, and use of caffeine, nicotine and other drugs. In most cases, bruxism is mild and does not require treatment. When bruxing is more frequent however it can lead to jaw disorders, headaches, earaches, damaged teeth, chronic facial pains, and other problems. Therapy such as muscle relaxers and botox are currently used as remedies for bruxism. Alleged dental solutions include mouth guards and splints which appear to be designed to prevent damage to the teeth or decrease muscle activity. For example, U.S. Pat. No. 7,004,172 to Zacco shows a device which seeks to separate a user's mandibular and maxillary teeth by creating a space in the posterior portion of said mandibular and maxillary teeth. U.S. Pat. No. 6,886,566 to Eubank shows a device having a multiplicity of arches which act to maintain the tempromandibular joint in the proper position in an attempt to prevent bruxing. U.S. Pat. No. 6,675,804 to Pivovarov shows a device which maintains the tongue and mandibular and maxillary teeth in a position which seeks to eliminate the potential for bruxing. However, the device in Pivovarov encompasses both the mandibular and maxillary teeth, and is bulky and uncomfortable. U.S. Pat. No. 6,604,528 to Duncan shows a device that contains guide elements to position the device relative to the mouth and teeth and at the same time appears to prevent mating of the teeth when the mouth is closed and therefore gnashing or grinding of teeth during sleep. Yet, such devices heretofore shown in the art that are aimed to prevent bruxism or damage caused by bruxing fail to address or effectively aid in the treatment of snoring, OSA and GERD. An object and feature of the instant invention is the separation of the posterior teeth thereby eliminating the possibility of clenching which is a prerequisite for bruxing, while nonetheless permitting nocturnal jaw movements.
Hence, an object of the instant invention is the presentation of an effective intraoral appliance for treatment of sleep disorders including snoring, OSA, GERD or bruxing by moving the user's mandible forward with respect to the user's maxilla in order to open the airway in a manner which is comfortable, easily placeable, and without adverse effects. As shown above, prior devices have struggled to optimize the size and design parameters to facilitate the dual goals of comfort and effectiveness, but have woefully failed to achieve this goal. Thus, compliance is a predominant issue.